103规约提供了继电保护设备（或测控设备）的信息接口规范。本标准适用于将继电保护和测量控制功能组合在一个设备内，只有一个通讯口的设备的信息接口，以及继电保护和测量控制功能分别由不同设备完成其功能的设备的信息接口。本规约属于问答式规约。在任何情况下，子站都不准主动向主站发送信息。-Statute 103 provides the relay protection equipment (or measurement and control equipment) interface specification information. This standard applies to the relay protection and measurement control functions combined in one device, only the mouth of a communications device information interface, as well as control functions of relay protection and measurement equipment by different equipment to complete its function of information interfaces. This Statute, the Statute are questions and answers. In any case, the sub-station were not allowed to take the initiative to send a message to the master station.